Asha Philip is the only British representative in the women's shorter sprint.

Gemili, 21, injured his hamstring when competing in Birmingham last month after running his first sub 10-second time.

Dina Asher-Smith explains why she is only competing in the 200m despite also qualifying for the 100m

Who else is in?

Former Olympic champion and London 2012 silver medallist Christine Ohuruogu, 31, will aim to retain her 400m title and seal a third crown, having first won it in 2007.

Elsewhere, 400m runner Martyn Rooney will compete in the relay but not the individual event.

Olympic, Commonwealth and European long jump champion Greg Rutherford is hoping to become only the fifth British athlete - after Daley Thompson, Sally Gunnell, Jonathan Edwards and Linford Christie - to achieve an athletics Grand Slam in China by holding all four major titles.

Ennis-Hill will be joined in the heptathlon by medal rival Katarina Johnson-Thompson, who will also compete in the long jump.

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Shara Proctor sets British long jump record at Anniversary Games

Ennis-Hill's coach Toni Minichello said Britain has "some incredible talent" in multi-discipline events and that Johnson-Thompson and Morgan Lake - who was selected for the high jump - are "way better than Jessica was at the same age".

Former heptathlete Kelly Sotherton told BBC Radio 5 live: "Jess has basically sent out a big message to the rest of the heptahlon fraternity to say 'I'm back and I'm going to Beijing to win gold' and I don't expect her to go for anything less."

Farah will be aiming to complete a hat-trick of world 5,000m titles after taking gold in 2011 and 2013.

Long jumper Shara Proctor has also been selected after setting a British record of 6.98m at the Olympic Stadium on Saturday.

Who is out?

Long-distance runner Andy Vernon, who has had spats on social media with GB team-mates Farah and 800m Commonwealth Games silver medallist Lynsey Sharp in the past, said he was "really disappointed" to be left out.

He failed to meet the qualifying standard for the 5,000m and did so only once for the 10,000m event. "Maybe one day someone in British Athletics will believe in me," he added.

Britain's number one steeplechaser Lennie Waite said she planned to appeal against her omission from the squad. Despite running under the qualifying time for Beijing, rules state she must do this twice.

Steeplechaser Lennie Waite is appealing against her omission from the squad

"I am no stranger to failure," Waite said. "However, I am in the midst of the best track season of my life and I feel I deserve to reap the rewards of my persistence, improvement, and dedication.

"Instead, I feel powerless and undervalued. I live for a challenge and this is just one more barrier that I must hurdle."

What are the rules?

To qualify for selection, athletes must either be a reigning World or European champion, or finish in the top two at the British Championships and hit the qualifying times twice.

If an athlete makes the qualifying time once, they may still be selected if the British Athletics selection panel feel they have "realistic potential to finish in the top eight in their event" in Beijing, or they are "a developing athlete" who is progressing towards future Olympic medal success.

All athletes have 24 hours from the squad being announced - so until 14:00 BST on Wednesday, 29 July, to lodge an appeal. They can do so on the basis of two reasons. One, that the selection policy has not been followed. Or two, that there has been a factual error in the selection decision. Appeals will be ruled on swiftly, likely to be by the end of the week.

What about the 'plastic Brits'?

Zharnel Hughes (200m) and Cindy Ofili (100m hurdles) are selected after qualifying in their first outing as GB athletes since becoming eligible in June.

Hughes, 19, and Ofili, 20, who have held British nationality since birth but have been described as "plastic Brits", secured their places at the British Championships in Birmingham earlier this month.

Ofili's sister Tiffany Porter, 27, who holds dual US and British nationality and switched allegiance to GB in 2010, is also selected in the 100m hurdles.

Tiffany Porter took bronze in the 2013 Worlds 100m hurdles and will compete against her sister Cindy Ofili, 20, in the same event

What has been the reaction?

Triple jumper Nathan Douglas said he had left himself "vulnerable to others' belief, faith and decision" after not making the squad.

Sotherton said she was "sad" to see Douglas and 21-year-old long jumper Jazmin Sawyers not selected, tweeting: "It appears one standard fits some and not others".

Dina Asher-Smith also tweeted to thank British Athletics and say she "can't wait" for Beijing

James Ellington, 29, is part of the 4x100m relay squad, but commiserates with Nigel Levine, 26, who was part of the 4x100 in Daegu in 2011, but has not been selected for Beijing

The 4x100m relay is at the end of the World Championships, giving Gemili an extra week to recover from injury

Katarina Johnson-Thompson, 22, is doing the heptathlon alongside Ennis-Hill, and the long jump. She came fifth in the heptathlon in Moscow in 2013

Meghan Beesley, 25, was selected for the 400m hurdles. She reached the semi-finals at the last World Championships